Da-Da Da-Da Daaa --- Da-Da Da Da-Da Da Daaa
Da-Da Da-Da Daaa --- Da-Da Da Da-Da Da Daaa
Twilight Sparkle awoke from her slumber, stretching her legs with a pop. She hopped out of bed with a smile on her face, eager to confront the day. After her usual morning hygiene ritual, she went down the stairs to the kitchen, where her faithful assistant/brother/son was already eating a bowl of cereal.
"Morning, Spike! Enjoying your breakfast?" she asked.
Spike nodded an affirmative, shoving another spoonful of Technicolor Wheat Flakes into his mouth.
Rolling her eyes, Twilight fixed a bowl for herself, as well a fresh apple, and sat herself down next to him. Once she had finished eating, she waved Spike goodbye, grabbed her saddlebags, and set out on her usual Thursday errands.
However, the second she stepped outside the large front gates to her home, it became instantly apparent that something about this morning was indeed unusual. For there was an incredibly catchy beat traipsing by on the breeze. Twilight couldn't help but start humming along. The song, whatever it was, seemed to fit her mood perfectly.
Trotting along towards Barnyard Bargains, she couldn't help but get lost in the music, closing her eyes as she matched the high-pitched tones. Completely zoned out, she failed to hear the pony approaching her at speed. So, she ended up walking headfirst into them, producing a soft 'pomf' barely audible over the music.
Blinking herself out of her stupor, Twilight beheld the orange, Stetson-capped form of Applejack. Curiously, Applejack was also humming the same tune she was, despite the sweat that has started beading off her hair and the frantic expression on her face.
Twilight reacted in the manner as was expected, that being asking her what was wrong.
But when she tried to speak, Twilight found that she was unable to stop humming.
Oh, ok, Twilight thought. This was just one of those Heartsongs which happened occasionally. Realizing this, she didn't bother trying to reply while the song was still going, and instead tilted her head quizzically at Applejack while continuing to hum.
Applejack gestured frantically in the direction of Town Hall, then immediately turned around and galloped off. Twilight, now somewhat concerned, took to the air and followed, unable to keep up on hoof.
Soon, they arrived. The scene playing out in the center of Ponyville was surreal, to say the least. It looked as if a good quarter of everypony in town was present, and all were humming the same catchy beat. However, in contrast to the song's largely uplifting nature, most wore expressions of complete panic on their faces.
Upon witnessing her show up, most of the crowd rushed over and surrounded her with their fearful stares, forming a harmonious acapella beat. Pinkie, Big Mac, and Applebloom were there, but none of her other friends were among the mass of bodies. They were probably still sleeping. Pinkie in particular was keeping herself busy by running around and handing everypony large glittery notebooks and markers.
Twilight shot her an approving look for her good thinking. Ponies were using the notebooks to write messages to eachother, as their mouths were otherwise occupied. Most of the pages she could see displayed some variant of either 'What's going on?' or 'I don't know!'. The Flower Trio, meanwhile, had all collapsed, clutching pages that read 'THE HORROR!!!' even as they continued to hum.
Preempting her inevitable inquiry, Pinkie appeared in front of Twilight, shoving her notebook in the alicorn's face. It read: 'Normally, I'm all for a catchy musical number, but this is ridiculous! We've been stuck humming this song for like THREE HOURS!'
Nevermind, Twilight thought. This was most certainly not ok. If this really was a Heartsong, there was nothing anypony could do to interrupt it until it was over. They were caused by harmonic resonance with the very mana leylines that suffused the entire planet! As long as the song was still going, anyone within earshot wouldn't be able to resist humming along. And then they would be stuck.
She needed answers. Grabbing a notebook in her magic, she quickly wrote down 'Do we know what song this is? Or who began humming it first?'
After reading her questions, Applejack scrawled out a reply and angled it to Twilight. 'It's apparently Guile's Theme from one of those new-fangled video games. A colt named Button Mash started it.'
Nodding, Pinkie added 'Fluttershy is in the middle of flying him home right now. There's this huge mob of meanie ponies who really, really wanna beat him up!'
'Yeah, they also completely destroyed the arcade,' wrote Applejack. 'I haven't seen everypony this riled up in a while.'
Twilight had to let those bits of info sink in. 'Ok, so I should probably get somepony to go calm them down soon,' she wrote. 'But now I'm wondering why the song hasn't ended yet.'
It was then that Twilight felt somepony poking her leg. Looking down, she saw Applebloom, busy writing. The filly showed her when she was finished. 'Button Mash says it's cuz game songs play on a loop.'
Twilight slammed a hoof to her face. Why didn't she realize that earlier? She wrote a reply with her magic. 'Great. So, we could conceivably be humming this for the rest of our lives. Or at least until whatever condition turned this into a Heartsong fulfills itself. But considering we're all still humming in the middle of a mass panic, that probably isn't happening.'
After they had finished reading, the mood of all the other ponies in the area lessened even further. Applejack rubbed her shoulder awkwardly.
Breaking the 'silence' was Big Mac, whose notebook read 'Twilight, perhaps one of your many potent works of arcane spellcraft could be utilized for the purpose of ending this dastardly melody.'
Once Twilight had shaken off her surprise at Big Mac's surprisingly eloquent written vocabulary, she lowered her head and wrote 'This is a magical problem out of anypony's league. To stop Guile's Theme now would require the equivalent effort of reversing gravity for the entire country at once. The best I could do right now would be a selective hearing spell; we'd all still be humming, just unable to hear it. (You have no idea how helpful that spell was during my education.)'
Pinkie threw her legs up into the air. 'Come on, Twilight! You're the smartest mare I know! You have to do something! I haven't even eaten breakfast yet!'
Twilight rolled her eyes. 'Of course I can fix it, I'll just have to do some research into more unconventional methods first.'
'Well, step on it!' Pinkie exclaimed.
Then, Applebloom added 'Don't mind her, Twilight, there's no rush.'
Applejack turned down to face her and knit her brow. 'No rush? Of course there's a rush! You're just trying to get out of school.'
In response to this accusation, Applebloom blinked sheepishly and turned away.
'Whatever,' wrote Twilight. 'Just give me an hour. And make sure nopony leaves town. We don't want this to spread.'
Big Mac gave her a salute. 'You can count on us, Twilight.'
Assured everything would be fine in her absence, Twilight waved goodbye and teleported home in a flash.
* Precisely One Hour Later *
Twilight Sparkle returned with full saddlebags. Now, with all of Ponyville crowded around Town Hall, Guile's Theme had gotten really loud. Even Button Mash was there, and only Cloudkicker was beating him up, which was a good sign.
Once Twilight had drawn their attention with a magical firecracker, Trixie style, she pulled out her notebook and wrote 'Ok, everypony, I've come up with some options as to how to fix this. The issue is that they're all unthinkable.'
After levitating the message so everypony could read it, she produced five manila folders and set them on the ground in front of her. Each was labeled with the word Option and a number.
Twilight opened the first folder. The page inside read: 'I turn everypony into plants, since plants can't sing. Then Princess Celestia changes us all back, assuming she finds us, and hopefully the song doesn't start up again.'
As far as the eye could see, ponies were vehemently shaking their heads. Well, except for Fluttershy.
Twilight nodded. She opened the second folder. It read: 'We ask Discord to help. Knowing him, though, even if he does agree, he'll probably complain about if for a while. Or just change it to The Song that Gets on Everybody's Nerves because he'd find this whole situation very funny.'
Same reactions all around. Including Fluttershy's.
Twilight opened folder number three. 'I cast a Mute spell on everypony in town, and we'll lose our voices. The issue is that the unicorn who wrote the spell really hated his wife, so the effects are permanent.'
This garnered more mixed reactions. Some ponies, such as Pinkie, were still shaking their heads no, but others just shrugged or tilted their heads back and forth. Fluttershy and DJ PON-3 were nodding.
Then came the fourth folder. 'We all pick up roots and go live inside one of those enchanted comic books. I can't cast the enchantment myself, though, and the only option that's permanent is this dangerous-seeming one I haven't read called Sword Art.'
Nopony looked excited about that one, save Rainbow Dash. Judging by her pantomimed retching, Fluttershy looked especially against the idea.
And finally, option five. 'I do nothing, and we all die slowly and painfully from dehydration, since we can't eat and sing at the same time. But at least we'll know peace in Elysium.'
Looks of shock blossomed across the muzzles of everypony present. Jaws likely would have hit the floor, were they not all being used.
'Yeah, I figured as much,' wrote Twilight. 'Option Three it is, then.'
* * *
(Ok, reader, you can stop playing the theme now. Feel free to keep it on if you want, though. It's good.)
Later that day, Princess Celestia was enjoying her well-earned afternoon tea break in her study when a wisp of smoke entered through the window. Materializing in green dragonfire, a pair of scrolls fell onto her desk. Curiosity regarding what her former student had just sent her compelling her to act now, she set down her cup and opened the first one with her magic. It was written on much higher quality parchment than Twilight usually used.
Her brow knitted when she saw the contents. It was an official Royal Decree, effective immediately. Such a thing was unlike Twilight, Celestia thought. She had never exercised this most absolute of her political powers before, so as not to undermine the common pony and bypass the modern legislative system. However, the contents of the decree itself was even more baffling.
By the order of Her Royal Highness, Princess Twilight Sparkle, all arcade cabinets of the game Street Fighter II are to be immediately relinquished to the Crown and destroyed. No further copies of the game may be produced. Additionally, any verbal mention of the game or its contents will be considered an act of high treason, with punishment meted out accordingly. Also, Yoko Philharmonia and Island Abe are each sentenced to the dungeon for one million years.
Shaking her head in confusion, Celestia opened the second letter. Perhaps it would offer some clarification.
So, long story short, everypony in Ponyville is mute now. Expect a follow-up letter tomorrow when I'm not completely exhausted from mass spellcasting.
Twilight Sparkle
Celestia blinked. She took a deep breath. Abruptly, her royal snout connected with the surface of the table.
Author's Note
Yes, I know this is really stupid. No, I do not care. Deal with it. 
Funny story, the original ending had Option Five as the only possibility. But then I realized no one but me would actually like that ending, so I changed it. The one good bit was that the Mane 6 each wrote a last request for Celestia, and Rainbow's was great:
Yo, it's Rainbow Dash. Could you do me a favor and, like, build a humungous golden statue of me somewhere? That way, nopony will forget how awesome I was. Also, sheesh, dying of thirst sucks.
Dash
